#include<iostream>
using namespace std;
int main()
{
	int n;
	while (cin >> n)
	{
		int ans = 1;
		for (int i = 0; i < n; i++)
		{
			int temp = 0;
			cin >> temp;
			if (temp % 2 == 1) {
				ans *= temp;
			}
		}
		cout << ans << endl;
	}
	return 0;
}